Science & technology

Study: Moss Spores Survive 9 Months in Space

A breakthrough proving life's cosmic resilience, or an ethical threat to undiscovered alien ecosystems?

Published NOV 20 2025

Study: Moss Spores Survive 9 Months in Space

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Image credit: Unsplash

The Facts

Researchers from Hokkaido University sent moss sporophytes to the International Space Station in March 2022, where astronauts attached the samples to the exterior of the station for 283 days of direct space exposure before returning them to Earth in January 2023.
Discover Wildlife
IFLScience
SciTech Daily
According to their results published in iScience on Thursday, over 80% of the moss spores survived nine months of direct exposure to space conditions, including cosmic radiation, extreme temperature fluctuations ranging from -320°F to -131°F and microgravity.
Cell Press
Science News
Gizmodo
Of the spores that survived space exposure, 86% of those fully exposed to ultraviolet radiation germinated successfully, while 97% of those shielded from UV radiation but exposed to other space conditions germinated.
PHYS
Interesting Engineering
Time
Laboratory testing before the space mission revealed that moss sporophytes exhibited approximately 1,000 times greater tolerance to ultraviolet radiation than brood cells. In contrast, juvenile moss structures could not survive high UV levels or extreme temperatures.
EurekAlert!
SciTech Daily
Livescience.Com on X
The protective structure surrounding the moss spores, called a sporangium, acts as a natural barrier that absorbs UV radiation and provides physical and chemical protection, which researchers believe enabled bryophytes to transition from water to land 500 million years ago.
Guardian
The Scientist
Gizmodo
Mathematical modeling based on experimental data suggests that moss spores could survive in space conditions for up to 15 years. However, researchers emphasize this is a preliminary estimate that requires additional data for confirmation.
NBC
Popular Science
USA Europe Asia on X

Sources Split

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RIGHT

ESTAB
CRIT

CENTER

PRO
ESTAB

The Spin

Techno-optimist narrative

Space-exposed moss spores prove life can endure the harshest conditions imaginable. This breakthrough demonstrates that life is incredibly robust and could persist across vast cosmic distances. Evolution equipped these organisms with natural survival pods that make interplanetary life transfer genuinely possible.

New Scientist

Techno-skeptic narrative

Terraforming Mars with hardy moss species raises serious ethical concerns about destroying potential alien ecosystems. Transforming entire planets for human occupation could eliminate existing microbial life and create irreversible environmental damage. The rush to colonize other worlds ignores fundamental questions about planetary stewardship.

Space.com

Narrative C

Moss is a climate superhero. It absorbs four times more CO₂ than trees, needs no soil, survives scorching heat and cools cities through evaporation. While humans rip it off walls, moss quietly filters pollution, releases oxygen and fights erosion. Instead of killing humanity's best ally or sending it to space, the world must embrace moss roofs, walls and carpets for a greener, cooler future — on Earth.

Massimo on X